Label	Element	Value
Discovery Portfolio
Risk/Return:	rr_RiskReturnAbstract
Supplement to Prospectus [Text Block]	rr_SupplementToProspectusTextBlock	Prospectus Supplement March 16, 2022 Morgan Stanley Institutional Fund Trust Supplement dated March 16, 2022, to the Morgan Stanley Institutional Fund Trust Prospectuses dated January 28, 2022 Discovery Portfolio Dynamic Value Portfolio Global Strategist Portfolio (the "Funds") The following changes will take effect on April 29, 2022: • Class IS shares of the Funds will be renamed Class R6 shares; • The minimum initial investment amount for Class I shares of the Funds will be reduced to $1 million; • The minimum initial investment amount for Class R6 shares of the Funds will be reduced to $5 million; • The contingent deferred sales charge holding period for Class A shares of the Funds that are not subject to any sales charges at the time of purchase will be reduced to 12 months after purchase; and • The dollar amount at which investors may qualify for a sales charge discount for Class A shares of a Fund will be increased to $50,000. Accordingly, the cumulative net asset value per share of Class A shares of a Fund being purchased in a single transaction (together with other shares of Morgan Stanley Funds), as described in the section "Fund Summary—Fees and Expenses" in the Prospectus, at which investors may qualify for a sales charge discount will be $50,000 or more. In addition, the front-end sales charge schedule for Class A shares of the Funds as well as the dealer commission as a percentage of offering price schedule will be amended. Accordingly, the following changes will be made to each Prospectus effective April 29, 2022: Each instance of "Class IS" in each Prospectus is hereby deleted and replaced with "Class R6."
Risk/Return [Heading]	rr_RiskReturnHeading	Discovery Portfolio
Expense Narrative [Text Block]	rr_ExpenseNarrativeTextBlock	In the section of the Prospectus entitled "Fund Summary—Fees and Expenses", the dollar amount at which investors may qualify for a sales charge discount for Class A shares of a Fund will be increased to $50,000 or more. Footnote 1 in the section of each Prospectus entitled "Fund Summary—Fees and Expenses" is hereby deleted in its entirety and replaced with the following: Investments in Class A shares that are not subject to any sales charges at the time of purchase are subject to a contingent deferred sales charge ("CDSC") of 1.00% that will be imposed if you sell your shares within 12 months after purchase, except for certain specific circumstances. See "Shareholder Information—How To Redeem Fund Shares" for further information about the CDSC waiver categories. Please retain this supplement for future reference.
Expense Breakpoint Discounts [Text]	rr_ExpenseBreakpointDiscounts	In the section of the Prospectus entitled "Fund Summary—Fees and Expenses", the dollar amount at which investors may qualify for a sales charge discount for Class A shares of a Fund will be increased to $50,000 or more.
Expense Breakpoint, Minimum Investment Required [Amount]	rr_ExpenseBreakpointMinimumInvestmentRequiredAmount	$ 50,000
Discovery Portfolio \| Class A Shares
Risk/Return:	rr_RiskReturnAbstract
Expenses Deferred Charges [Text Block]	rr_ExpensesDeferredChargesTextBlock	Investments in Class A shares that are not subject to any sales charges at the time of purchase are subject to a contingent deferred sales charge ("CDSC") of 1.00% that will be imposed if you sell your shares within 12 months after purchase, except for certain specific circumstances.

Include the narrative explanations in the order indicated. A Fund may modify the narrative explanations if the explanation contains comparable information to that shown. The narrative explanation regarding sales charge discounts is only required by a Fund that offers such discounts and should specify the minimum level of investment required to qualify for a discount.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 3
-Subsection instructions
-Paragraph 1
-Subparagraph b

+ Details

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Namespace Prefix:	rr_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

This element represents the minimum level of investment required to qualify for discounted sales charges or fund expenses (SEC Form N-1A 2006-09-14 A.3.instructions.1.b).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 3
-Subsection instructions
-Paragraph 1
-Subparagraph b

+ Details

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Namespace Prefix:	rr_
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Period Type:	duration

- Definition

This table describes the fees and expenses that you may pay if you buy, hold, and sell shares of the Fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below. You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $[ ] in [name of fund family] funds. More information about these and other discounts is available from your financial intermediary and in [identify section heading and page number] of the Fund's prospectus and [identify section heading and page number] of the Fund's statement of additional information

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 3
-Subsection instructions
-Paragraph 1
-Subparagraph b

+ Details

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- Definition

A Fund may include in a footnote to the table, if applicable, a tabular presentation showing the amount of deferred sales charges (loads) over time or a narrative explanation of the sales charges (loads) (e.g., __% in the first year after purchase, declining to __% in the __ year and eliminated thereafter).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 3
-Subsection instructions
-Paragraph 2
-Subparagraph a
-Clause i

+ Details

Name:	rr_ExpensesDeferredChargesTextBlock
Namespace Prefix:	rr_
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- References

No definition available.

+ Details

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Namespace Prefix:	rr_
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- Definition

Risk/Return Summary Investment Objectives/Goals Include the following information, in plain English under rule 421(d) under the Securities Act, in the order and subject matter indicated

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 2

+ Details

Name:	rr_RiskReturnHeading
Namespace Prefix:	rr_
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- Definition

This element contains the text of a prospectus supplement (submission type 497) not already contained in an element containing amended text or other data from a previous submission.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form
-Number N-1A

+ Details

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